The invention relates to well isolation systems including one or more valves actuatable by command signals.
In a wellbore, one or more valves may be used to control flow of fluid between different sections of the wellbore. The different sections may include multiple completion zones in vertical or deviated wells or in multilateral wells. Various types of valves have been used to control fluid flow, including formation isolation valves that are actuatable open or shut to allow access to sections of the wellbore. In one configuration, a formation isolation valve may include a ball valve rotatable to open and closed positions. The ball valve includes a bore that when in the open position is aligned to the bore of tubing in the well so that fluid communication can be established in well sections above and below the ball valve.
During completion operations, the formation isolation valve may initially be kept shut to isolate the wellbore section downstream from the valve. When a completion task (such as perforating operations) needs to be performed in the downstream section, the formation isolation valve may be opened and a completion tool (e.g., a perforating gun) can be lowered through the bore of the ball valve in the formation isolation valve to the downstream section for operation. Examples of other completion tools include tools for setting packers and bridge plug tools for sealing plugs at predetermined depths. Once the completion task is performed, the completion tool may be removed from the downstream section, with the formation isolation valve closed after removal of the tool to again isolate the downstream wellbore section.
With some formation isolation valves, a mechanical operator mechanism may be used to open or shut the formation isolation valve. Such mechanical operator mechanisms may include a shifting tool that engages a valve operator in the formation isolation valve to rotate the ball valve between the open and closed positions. A shifting tool typically may include a latching profile to engage a corresponding profile of the valve operator in the formation isolation valve. However, such an engagement profile may cause the shifting tool to catch onto debris or other downhole surfaces as the shifting tool is moved in the well. This may cause the shifting tool to be stuck downhole which may render retrieval of the completion tool difficult or impossible. Another potential issue is that, as the shifting tool is raised and lowered in the wellbore, the engagement profile of the shifting tool may be damaged due to rubbing contact to surfaces downhole, which may decrease the reliability of shifting tool operation of the formation isolation valve.
Thus, a need arises for an improved operator mechanism to actuate equipment, such as formation isolation valves, in a wellbore.